U.S. patent number 8,151,046 [Application Number 12/370,846] was granted by the patent office on 2012-04-03 for disk array apparatus and method for controlling the same.
This patent grant is currently assigned to Hitachi, Ltd.. Invention is credited to Akihisa Hirasawa, Katsuyoshi Suzuki.
United States Patent |
8,151,046 |
Suzuki , et al. |
April 3, 2012 |
Disk array apparatus and method for controlling the same
Abstract
The disk array apparatus includes a controller having a
communication control unit for accepting a data input/output
request, a disk controller unit for controlling a plurality of disk
drives, and a cache memory for temporarily storing data transferred
between the communication control unit and the disk controller
unit. A plurality of cooling fans are provided for cooling the
plurality of disk drives. In response to receiving a request, the
controller controls the rotational speed of a first cooling fan
related to a first disk drive, which is related to the request, and
changes an operational mode of the first disk drive related to the
request such that the rotational speed of the first cooling fan is
increased before the operational mode of the first disk drive is
changed.
Inventors: |
Suzuki; Katsuyoshi (Odawara,
JP), Hirasawa; Akihisa (Odawara, JP) |
Assignee: |
Hitachi, Ltd. (Tokyo,
JP)
|
Family
ID: |
33296755 |
Appl.
No.: |
12/370,846 |
Filed: |
February 13, 2009 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20090150609 A1 |
Jun 11, 2009 |
|
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
11056005 |
Feb 14, 2005 |
7523258 |
|
|
|
10659398 |
Sep 11, 2003 |
7080201 |
|
|
|
Foreign Application Priority Data
|
|
|
|
|
May 22, 2003 [JP] |
|
|
2003-145111 |
|
Current U.S.
Class: |
711/112;
714/6.22; 710/27; 711/114; 710/28; 710/22 |
Current CPC
Class: |
G11B
27/34 (20130101); H05K 7/20836 (20130101); G06F
3/0661 (20130101); G06F 3/0658 (20130101); G06F
3/0607 (20130101); G06F 3/0689 (20130101); G11B
27/36 (20130101); G06F 3/0625 (20130101); G11B
27/002 (20130101); G11B 33/144 (20130101); Y02D
10/154 (20180101); Y02D 10/00 (20180101); G11B
2220/415 (20130101) |
Current International
Class: |
G06F
12/00 (20060101) |
Field of
Search: |
;711/112,114
;710/22,27,28 ;714/6.22 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
0795824 |
|
Sep 1997 |
|
EP |
|
0844561 |
|
May 1998 |
|
EP |
|
1001345 |
|
May 2000 |
|
EP |
|
1315074 |
|
May 2003 |
|
EP |
|
02-188835 |
|
Jul 1990 |
|
JP |
|
02188835 |
|
Jul 1990 |
|
JP |
|
05-150909 |
|
Jun 1993 |
|
JP |
|
5150909 |
|
Jun 1993 |
|
JP |
|
09-330182 |
|
Dec 1997 |
|
JP |
|
9330182 |
|
Dec 1997 |
|
JP |
|
09330184 |
|
Dec 1997 |
|
JP |
|
10311720 |
|
Nov 1998 |
|
JP |
|
2001-100922 |
|
Apr 2001 |
|
JP |
|
2001-142650 |
|
May 2001 |
|
JP |
|
2001142650 |
|
May 2001 |
|
JP |
|
2001167040 |
|
Jun 2001 |
|
JP |
|
2001-211411 |
|
Aug 2001 |
|
JP |
|
2001-356883 |
|
Dec 2001 |
|
JP |
|
2001337868 |
|
Dec 2001 |
|
JP |
|
2002150746 |
|
May 2002 |
|
JP |
|
2002/ 333954 |
|
Nov 2002 |
|
JP |
|
2002333954 |
|
Nov 2002 |
|
JP |
|
2003-036146 |
|
Feb 2003 |
|
JP |
|
200336146 |
|
Feb 2003 |
|
JP |
|
2004-178557 |
|
Jun 2004 |
|
JP |
|
2004178557 |
|
Jun 2004 |
|
JP |
|
99/50754 |
|
Oct 1999 |
|
WO |
|
Other References
Serial Attached SCSI and Serial ATA Compatibility, Intel, 2002, pp.
1-8. cited by other .
ESG Product Brief EMC, Mar. 2003, CIARiiON With ATA, pp. 1-2. cited
by other .
EMC CLARiiON Backup Storage Solutions Back-up-to-Disk Guide with
LEGATO Networker Diskbackup Option (DBO), Engineering White Paper,
Apr. 8, 2003, pp. 1-28. cited by other .
EMC CLARiiON Backup Storage Solutions Backup-to-disk Guide with
Computer Associates' BrightStor ARCserve Backup, Engineering White
Paper, Apr. 16, 2003, pp. 1-28. cited by other .
EMC CLARiiON Backup Storage Solutions Backup-to-Disk: An Overview,
Engineering White Paper, Mar. 3, 2003, pp. 1-10. cited by other
.
EMC CLARiiON Backup Storage Solutions Backup-to-Disk Guide with
CommVault Galaxy, Engineering White Paper, Mar. 3, 2003, pp. 1-26.
cited by other .
EMC CLARiiON Backup Storage Solutions Backup-to-Disk Guide with
Computer Associates BrightStor Enterprise Backup, Engineering White
Paper, Apr. 16, 2003, pp. 1-23. cited by other .
IBM Technical Disclosure Bulletin vol. 38, No. 7, Jul. 1995 (New
York), "Foreground/Background Checking of Parity in a Redundant
Array of Independent Disks-5 Storage Subsystem", pp. 455-458. cited
by other .
Laboratory Automation and Information Management 32, 1996,
(Elsevier Science B.V.), R E Dessey, "Computer Connections", pp.
53-62. cited by other .
EMC 2-Gigabit Disk-Array Enclosure EMC Corporation (DAE2), FC and
ATA Models, Hardware Reference P/N 014003048, Rev A02. cited by
other .
SGI InfiniteStorage TP9300S Storage Array, Data Sheet, available
at: http://www.sgi.com/pdfs/3643.pdf. cited by other .
Adaptec FS4500 Fibre to SATA RAID, Data Sheet, available at:
http:/www.sunstarco.com/PDF%20Files/Adaptec%20FS4500%20SATA.pdf.
cited by other .
Infortrend EonStor A16F-R1211/S1211 FC-to-SATA RAID Subsystem
product information, available at:
http://www.infortrend.com/2.sub.--product/a16f-r(s)1211.asp. cited
by other .
Synetic Inc., SyneRAID -800SA, SCSI/Fibre-toSATA RAID Subsystem
product information, available at:
http://www.synetic.net/Synetic-Products/SyneRAID-Units/SyneRAID-800SATA/S-
yneRAID-800SA.html. cited by other .
"SATA Disk System and Expansion of Unit offer 3.5 TB storage",
Product News Network, Nov. 1, 2004. cited by other .
JP 2003-145111, Office Action dated Oct. 2, 2007, English
translation of relevant portion, 7 pages. cited by other .
Judd, Ian, "Device Services Interface", Online, Jun. 19, 1996, pp.
1-8. cited by other .
"Veritas Volume Manager Storage Administrator 3.2, Administrator's
Guide", Veritas Software Corporation, Online, Jul. 2001, pp. 1-184.
cited by other .
SGI InfiniteStorage TP9300S Storage Array, Data Sheet, Copyright
2004, available at: http://www.sgi.com/pdfs/3643.pdf. cited by
other .
Adaptec FS4500 Fibre to SATA RAID, Data Sheet, Copyright 2003,
available at:
http:/www.sunstarco.com/PDF%20Files/Adaptec%20FS4500%20SATA.pdf.
cited by other .
Infortrend EonStor A16F-R1211/S1211 FC-to-SATA RAID Subsystem
product information, Oct. 8, 2005, available at:
http://www.infortrend.com/2.sub.--product/a16f-r (s)1211.asp. cited
by other .
Synetic Inc., SyneRAID -800SA, SCSI/Fibre-toSATA RAID Subsystem
product information, Oct. 10, 2005, available at:
http://www.synetic.net/Synetic-Products/SyneRAID-Units/SyneRAID-800SATA/S-
yneRAID-800SA.html. cited by other .
EMC 2-Gigabit Disk-Array Enclosure EMC Corporation (DAE2), FC and
ATA Models, Hardware Reference P/N 014003048, Rev A02, Feb. 2003.
cited by other .
Drive Swapping,
http://www.pcguide.com/ref/hdd/perf/raid/conf/advSwapping-c.html,
Apr. 17, 2001, 3 pages. cited by other .
External Storage Enclosures,
http://replay.waybackmachine.org/20011202064442/http://www.amtrade
. . . , Oct. 2001, 4 pages. cited by other .
HP A5856A RAID 4Si PCI 4-Channel Ultra2 SCSI Controller,
Installation and Administration Guide, Edition 3, Hewlett-Packard
Company, 2001, pp. 1-198. cited by other .
02-157r0 SAS Proposed Serial Attached SCSI working draft,
Information Technology--Serial Attached SCSI (SAS), Revision pre0,
Apr. 25, 2002, pp. 1-218. cited by other .
Serial ATA: High Speed Serialized AT Attachment, Revision 1.0, Aug.
29, 2001, Serial ATA Workgroup, pp. 1-306. cited by other .
Technology Presentation, "Serial Attached SCSI", Industry Working
Group, Dec. 2001, pp. 1-13. cited by other.
|
Primary Examiner: Bradley; Matthew
Attorney, Agent or Firm: Mattingly & Malur, PC
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a continuation application of U.S. Ser.
No. 11/056,005, filed Feb. 14, 2005 (now U.S. Pat. No. 7,523,258),
which is a continuation of application Ser. No. 10/659,398, filed
Sep. 11, 2003 (now U.S. Pat. No. 7,080,201), and which claim
priority to Japanese Patent Application No. 2003-145111, filed on
May 22, 2003, the contents of which all of which are incorporated
herein by reference in their entirety. This application is related
to U.S. Ser. No. 11/056,007, filed Feb. 14, 2005 (now U.S. Pat. No.
7,587,548), U.S. Ser. No. 11/056,006, filed Feb. 14, 2005 (now U.S.
Pat. No. 7,461,203), U.S. Ser. No. 11/055,994, filed Feb. 14, 2005
(now abandoned), U.S. Ser. No. 11/056,002, filed Feb. 14, 2005 (now
abandoned), U.S. Ser. No. 11/056,001, filed Feb. 14, 2005 (now
abandoned), and U.S. Ser. No. 11/055,968, filed Feb. 14, 2005 (now
abandoned), all of which are continuation applications of U.S. Ser.
No. 10/659,398, filed Sep. 11, 2003 (now U.S. Pat. No. 7,080,201)
and the contents of all of which are incorporated herein by
reference in their entirety.
Claims
What is claimed is:
1. A disk array apparatus, comprising: a controller having a
communication control unit for accepting a data input/output
request, a disk controller unit for controlling a plurality of disk
drives, and a cache memory for temporarily storing data transferred
between said communication control unit and said disk controller
unit; the plurality of disk drives being connected to the disk
controller unit to communicate with the disk controller unit, the
plurality of disk drives including a first disk drive; and a
plurality of cooling fans cooling the plurality of disk drives, the
plurality of cooling fans including a first cooling fan related to
the first disk drive, wherein in response to receiving a backup
request, the controller controls the rotational speed of the first
cooling fan and changes an operational mode of the first disk drive
related to the backup request such that the rotational speed of the
first cooling fan is increased before the operational mode of the
first disk drive is changed from a first mode of not storing data
related to the backup request to a second mode of storing data
related to the backup request.
2. The disk array apparatus according to claim 1, wherein: the
rotational speed of the first cooling fan is increased based on the
change in the operational mode of the first disk drive from a power
off mode to a ready mode.
3. The disk array apparatus according to claim 1, wherein: the
rotational speed of the first cooling fan is changed from a
low-power-consumption mode to a normal mode based on the change in
the operational mode of the first disk drive from a power off mode
to a ready mode.
4. The disk array apparatus according to claim 1, wherein: the
rotational speed of the first cooling fan is reduced based on the
change in the operational mode of the first disk drive from a ready
mode to a power off mode.
5. A disk array apparatus, comprising: a controller controlling a
Redundant Array of Inexpensive Disks (RAID) function; a plurality
of disk drives including a first disk drive; and a cooling fan
related to the first disk drive, wherein in response to receiving a
backup request, the controller controls the rotational speed of the
cooling fan and changes an operational mode of the first disk drive
related to the backup request such that the rotational speed of the
cooling fan is increased before the operational mode of the first
disk drive is changed from a first mode of not storing data related
to the backup request to a second mode of storing data related to
the backup request.
6. The disk array apparatus according to claim 5, wherein: the
rotational speed of the cooling fan is increased based on the
change in the operational mode of the first disk drive from a power
off mode to a ready mode.
7. The disk array apparatus according to the claim 5, wherein: the
rotational speed of the cooling fan is changed from a
low-power-consumption mode to a normal mode based on the change in
operational mode of the first disk drive from a power off mode to a
ready mode.
8. The disk array apparatus according to claim 5, wherein: the
rotational speed of the cooling fan is reduced based on the change
in the operational mode of the first disk drive from a ready mode
to a power off mode.
9. The disk array apparatus according to the claim 5, wherein: the
controller is included in a first housing, and the plurality of
disk drives and the cooling fan are included in a second housing
outside of the first housing.
10. A control method for a disk array apparatus having a
controller, a plurality of disk drives, including a first disk
drive, and a cooling fan related to the first disk drive, the
control method comprising: controlling, by the controller, a
Redundant Array of Inexpensive Disks (RAID) function; changing, in
response to receiving a backup request, the rotational speed of the
cooling fan and changing an operational mode of the first disk
drive related to the backup request such that the rotational speed
of the cooling fan is increased before the operational mode of the
first disk drive is changed from a first mode of not storing data
related to the backup request to a second mode of storing data
related to the backup request.
11. The control method according to the claim 10, wherein: in the
changing step, for changing the rotational speed of the cooling
fan, the rotational speed of the cooling fan is increased based on
the change in the operational mode of the first disk drive from a
power off mode to a ready mode.
12. The control method according to the claim 10, wherein: in the
changing step, for changing the rotational speed of the cooling
fan, the rotational speed of the cooling fan is changed from a
low-power-consumption mode to a normal mode based on the change in
the operational mode of the first disk drive from a power off mode
to a ready mode.
13. The control method according to the claim 10, wherein: in the
changing step, for changing the rotational speed of the cooling
fan, the rotational speed of the cooling fan is reduced based on
the change in the operational mode of the first disk drive from a
ready mode to a power off mode.
14. The control method according to the claim 10, wherein: the
controller is included in a first housing, and the plurality of
disk drives and the cooling fan are included in a second housing
outside of the first housing.
Description
BACKGROUND OF THE INVENTION
The present invention relates to a disk array apparatus and a
method for controlling the disk array apparatus.
DESCRIPTION OF THE RELATED ART
The quantity of data to be processed by a computer system has been
abruptly increased in these years. As a disk array apparatus for
managing such a large quantity of data, there has recently come to
public attention a large-scale disk array apparatus wherein a file
system is coupled to a disk array apparatus of a RAID (Redundant
Arrays of Inexpensive Disks) management type called mid-range class
or enterprise class which offers a giant storage resource. For the
purpose of efficiently using and managing such a giant amount of
data, there has been developed a technique by which the disk array
apparatus and an information processor are connected by means of a
dedicated network (Storage Area Network, which will be referred to
as the SAN, hereinafter) to realize high-speed, large-amount access
to the disk array apparatus.
Meanwhile, in a related disk array apparatus, it has been common
that only a disk drive having a specific type of communication
interface is connected to one disk controller unit. On the recent
market, however, there are available various types of disk drives
which are different in their communication interface, access speed,
etc., i.e., in Standard, price, etc. And from the viewpoint of the
property, investment cost, etc. of a system to be operated, users'
increasing need is to freely combine such disk drives to form a
disk array system having a flexible arrangement. At the same time,
another need is to utilize an existing disk array system more
effectively by minimizing a modification in the arrangement of the
existing disk array system while allowing the aforementioned
flexible combination.
SUMMARY OF THE INVENTION
In view of such circumstances, it is therefore a major object of
the present invention to provide a disk array apparatus which can
respond to these needs, and also to provide a method for
controlling such a disk array apparatus.
In accordance with an aspect of the present invention, the above
object is attained by providing a disk array apparatus which
includes a controller and a plurality of disk drives. The
controller has a communication control unit for accepting a data
input/output request, a disk controller unit for controlling a disk
drive, and a cache memory for temporarily storing data transferred
between the communication control unit and the disk controller
unit. The plurality of disk drives have different communication
interfaces and are connected to the disk controller unit to
communicate with the disk controller unit.
In this case, the disk controller unit has at least functions of
controlling the operations of the plurality of disk drives having
different communication interfaces and monitoring the states or
modes of the disk drives, which will be explained later. The
communication interface is, for example, FC-AL (Fibre Channel
Arbitrated Loop) interface, serial ATA interface, SCSI1 (Small
Computer System Interface 1) interface, SCSI2 (Small Computer
System Interface 2) interface, SCSI3 (Small Computer System
Interface 3) interface, or ATA (AT Attachment) interface.
In this way, in the case of the disk array apparatus of the present
invention, various types of disk drives having different
communication interfaces, access speeds and storage capacities,
i.e., different Standards, prices, etc. can be combined with one
disk controller unit, and thus an existing disk array apparatus can
be effectively used while minimizing a modification in the
arrangement of the disk array apparatus.
Other objects and advantages of the present invention will become
clear as the following description of the invention advances as
detailed with reference to preferred embodiments of the invention
as shown in accompanying drawings.
In accordance with the present invention, there can be provided a
disk array apparatus wherein various types of disk drives different
in their communication interface, access speed, etc., i.e.,
Standard, price, etc. can be freely combined with one disk
controller unit, and thus an existing disk array apparatus can be
effectively used while minimizing a modification in the arrangement
of the disk array apparatus, and also can be provided a method for
controlling the disk array apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the present invention will now be
described in conjunction with the accompanying drawings, in
which:
FIGS. 1A and 1B are front and back views showing an entire
arrangement of a storage system in accordance with an embodiment of
the present invention;
FIGS. 2A and 2B are exploded perspective views of a structure of a
management terminal in the present embodiment;
FIGS. 3A and 3B show exploded perspective views of a physical disk
management table in the present embodiment;
FIG. 4 is a perspective view of an LU management table in the
present embodiment;
FIG. 5 shows an exemplary hardware arrangement of a disk array
apparatus in the present embodiment;
FIG. 6 is a circuit diagram of the disk array apparatus in the
present embodiment;
FIG. 7 shows an example of a setting display screen in the present
embodiment;
FIG. 8 shows an example of a disk drive management table in the
present embodiment;
FIG. 9 shows an exemplary of a hardware arrangement of the present
embodiment used as an SES drive;
FIG. 10 shows a circuit configuration of an additional casing A 30
which accommodates only a SATA drive in the present embodiment;
FIG. 11 is a flow chart for explaining the exchanging operation of
the SES drive in the present embodiment; and
FIG. 12 is a flow chart for explaining a processing sequence of
control of the operation of the disk drive and the cooling
capability of a cooling fan 66 in the present embodiment.
DESCRIPTION OF THE EMBODIMENTS
The present invention will be detailed in connection with
embodiments of the invention with reference to the accompanying
drawings.
1. Apparatus Arrangement
FIG. 1A is a front view of a disk array apparatus 10 to be
explained in an embodiment of the present invention, FIG. 1B is a
rear view of the disk array apparatus 10, FIG. 2A is a perspective
view when viewed from the front side of a basic casing 20 mounted
in the disk array apparatus 10, FIG. 2B is a perspective view when
viewed from the rear side of the basic casing 20, FIG. 3A is a
perspective view when viewed from the front side of an additional
casing 30 to be mounted in the disk array apparatus 10, and FIG. 3B
is a perspective view when viewed from the back side of the
additional casing 30.
As shown in FIGS. 1A and 1B, the disk array apparatus 10 includes a
rack frame 11 as its base. A plurality of stages of mount frames 12
are provided inside of left- and right-side inner surfaces of the
rack frame 11 as arranged to be stacked in a vertical direction,
each mount frame is formed in a back-and-front direction, and a
basic casing 20 and additional casings 30 are mounted along the
mount frames 12 to be drawn or inserted therein in a drawer-like
manner. As shown in FIGS. 2A and 2B, boards and units for offering
various types of functions to the disk array apparatus 10 are
mounted in the basic casing 20 and additional casing 30.
As shown in FIG. 2A, a plurality of disk drive units 52 each having
a disk drive 51 provided therein are mounted as arranged in a row
on the front upper stage of the basic casing 20. In the present
embodiment, the disk array apparatus 10 includes a plurality of
disk drives 51 having different communication interfaces. The disk
drive 51 is, e.g., of a type having a communication interface
having a communication function based on FC-AL Standard, SCSI1
(Small Computer System Interface 1) Standard, SCSI2 Standard, SCSI3
Standard, ATA (AT Attachment) Standard, or serial ATA (Serial ATA:
SATA) Standard.
A battery unit 53, a display panel 54 for displaying the operating
mode, etc of the disk drive 51, and a flexible disk drive 55 are
mounted on the front lower stage of the basic casing 20. A
secondary battery is built in the battery unit 53. The battery unit
53 functions as a backup power source which supplies power to the
board or unit when power supply from an AC/DC power supply 57 is
interrupted due to a power failure or the like. Display devices
including an LED indicator or lamp for indicating the operating
mode of the disk drive 51 are provided on the display panel 54. The
flexible disk drive 55 is used as when a maintenance program is
loaded.
As shown in FIG. 2B, one power controller board 56 is mounted on
each of both sides of the upper stage of the back side of the basic
casing 20. The power controller board 56 is connected to
communicate with the plurality of disk drives 51. The power
controller board 56 and the plurality of disk drives 51 are
connected by a loop communication line such as, e.g., a
communication line based on the FC-AL scheme (topology) to
communicate with each other.
Mounted on the power controller board 56 are a PBC (Port Bypass
Circuit) 160 for controlling an FC-AL 150 formed between the disk
drives 51 as well as a circuit for monitoring the states of the
AC/DC power supply 57 and disk drives 51, for controlling power
supply of the disk drives 51, for controlling the cooling
capability of a cooling device, for controlling display devices on
the display panel 54, and for monitoring the temperature of each
casing. In this connection, the cooling device is a device for
cooling the interior of the disk array apparatus 10 and the
interiors of the casings 20 and 30, such as, e.g., an intercooler,
a heat sink or an air-cooling type cooling fan.
A connector 67 for a fiber channel cable is provided to the power
controller board 56, and a fiber channel cable 91 forming part of
the line of the FC-AL 150 is connected to the connector 67. In this
connection, the details of the FC-AL 150 is incorporated, for
example, in JP-A-2001-167040 (corresponding to U.S. patent
application Ser. No. 09/608,151), JP-A-2001-337868, or
JP-A-2001-222385 (corresponding to U.S. patent application Ser. No.
09/758,684 published as U.S. Patent Application Publication
US2001/0014956A1).
As shown in FIG. 2B, two of the AC/DC power supplies 57 are mounted
side by side in a space defined by two of the power controller
boards 56 on the back sides of the upper stage of the basic casing
20. The AC/DC power supplies 57 supply power to the disk drives 51,
boards, unit, etc. The AC/DC power supplies 57 are connected to the
power controller boards 56 to supply power to the respective disk
drives 51 according to signals from the power controller boards
56.
For the purpose of getting security of the power supply of the
respective casings 20 and 30, in the present embodiment, two of the
power controller boards 56 and two of the AC/DC power supplies 57
have been redundantly mounted in the basic casing 20 and additional
casing 30 respectively. However, each power controller board 56 and
each AC/DC power supply 57 may be mounted to each of the
casings.
A breaker switch 64 for turning ON and OFF the output of the AC/DC
power supply 57 is provided to the AC/DC power supply 57.
As shown in FIG. 2B, two wind-assisted cooling fan units 58 are
mounted side by side as located under the AC/DC power supplies 57
respectively. One or more cooling fans 66 are mounted in the
wind-assisted cooling fan unit 58. The cooling fan 66 acts to
supply air into the casing or discharge air therefrom to expel heat
generated in the disk drives 51 or AC/DC power supply 57. In this
case, the basic casing 20 and additional casing 30, and the boards
and units mounted thereto are designed to be formed therein with
ventilating passages or ports for circulation of air within the
casings 20 and 30, enabling efficient discharging of heat within
the casing 20 to the outside thereof by the cooling fans 66.
Although the cooling fan 66 can be provided for each of the disk
drives 51, it is preferable to provide a large cooling fan 66 for
each casing because the necessary number of chips or units can be
reduced.
The wind-assisted cooling fan unit 58 is connected to a control
board 59 or wind-assisted cooling fan unit 58 by a control line 48
so that the control board 59 or power controller board 56 controls
the rotational speed of the cooling fan 66 of the wind-assisted
cooling fan unit 58 through the control line 48.
As shown in FIG. 2B, a single piece of control board 59 is mounted
onto the lower stage of the back side of the basic casing 20.
Mounted on the control board 59 are a communication interface with
the disk drives 51 mounted in the basic casing 20 and additional
casing 30, a circuit for controlling the operations of the disk
drives 51 (e.g., based on a RAID scheme) or for monitoring the
modes of the disk drives 51, and so on.
In the present embodiment, though the power controller board 56 is
provided to control the power supply to the disk drives 51 and the
cooling capability of the cooling device, such control may be
carried out by the control board 59.
In the present embodiment, further, an interface board 61 having a
communication interface function with a host computer 300 based on,
e.g., the SCSI Standard or fiber channel Standard, a cache memory
62 for storing therein data to be written or read out to or from
the disk drives 51, and so on are mounted on the control board 59.
However, these elements may be mounted to another board.
Mounted to the interface board 61 mounted on the control board 59
is an external connector 63 which is based on a predetermined
interface Standard of a fiber channel, a SAN (Storage Area Network)
or LAN (Local Area Network) according to the protocol such as
Ethernet (registered trademark), or SCSI for connection with the
host computer 300. The host computer 300 is connected to the
interface board 61 at the external connector 63 connected to a
communication cable 92.
In this connection, for the purpose of getting security of control
of the disk drives 51 of the basic casing 20, two of the control
boards 59 may be redundantly mounted.
As shown in FIG. 3A, a plurality of disk drive units 52 having disk
drives 51 accommodated therein are mounted in a row in the front
side of the additional casing 30. As shown in FIG. 3B, the single
power controller board 56 is mounted on each of right and left
sides of the back of the additional casing 30. Also provided in a
space defined by the two power controller boards 56 are two of the
AC/DC power supplies 57 side by side. Two of the cooling fan units
58 are mounted under the AC/DC power supplies 57 side by side. The
breaker switch 64 for turning ON or OFF the output of the
associated AC/DC power supply 57 is provided to the associated
AC/DC power supply 57.
As has been explained above, in the present embodiment, for the
purpose of getting security of the power supply of the additional
casing 30, the two power controller board 56 and the two AC/DC
power supplies 57 are redundantly mounted in the additional casing
30 side by side each two. However, the single power controller
board 56 and the single AC/DC power supply 57 can be mounted in the
additional casing. Further, the functions of the power controller
board 56 including the control of the power supply to the disk
drives 51 and the control of the cooling capability of the cooling
device may be provided to the control board 59.
FIG. 4 shows an example of the structure of the disk drive 51
accommodated in the disk drive unit 52. The disk drive 51 includes
a casing 70, a magnetic disk 73, an actuator 71, a spindle motor
72, a head 74 for reading or writing data, a mechanism control
circuit 75 for controlling the mechanical part of the head 74,
etc., a signal processing circuit 76 for controlling a data
read/write signal to the magnetic disk 73, a communication
interface circuit 77, an interface connector 79 through which
various commands or data are input or output, a power connector 80,
all accommodated in the casing 70.
The disk drive 51 is, for example, a 3.5-inch-sized magnetic disk
of a contact start/stop (CSS) type or a 2.5-inch-sized magnetic
disk of a load/unload type. The 3.5-inch magnetic disk has a
communication interface based on, e.g., SCSI1, SCSI2, SCSI3 or
FC-AL. The 2.5-inch magnetic disk, on the other hand, has a
communication interface based on, e.g., serial ATA or ATA.
When the 2.5-inch magnetic disk is accommodated in the casing 20 or
30 of the disk array apparatus 10, it may be accommodated in a
container having a 3.5 inch shape. With it, the shock resistance
performance of the magnetic disk can be increased. In this
connection, the 2.5- and 3.5-inch magnetic disks are different not
only in their communication interface but also in the I/O
performance, power consumption, life, etc. When compared with the
3.5-inch magnetic disk, the 2.5-inch magnetic disk has a bad I/O
performance and a short life. When compared with the 3.5-inch
magnetic disk, however, the 2.5-inch magnetic disk is superior
thereto in that it has less power consumption.
2. Hardware Arrangement of Disk Array Apparatus
FIG. 5 is a block diagram of a hardware arrangement of the disk
array apparatus 10 for explaining it as an embodiment of the
present invention.
As shown in FIG. 5, the disk array apparatus 10 is connected with
the host computer 300 via a SAN 200, and also connected with a
management computer 500 via a LAN 400. The host computer 300 is an
apparatus which accesses the disk array apparatus 10, such as a
personal computer, a work station or a mainframe computer. The
management computer 500, which is a computer for operating and
managing the disk array apparatus 10, is connected to the disk
array apparatus 10 via the LAN (Local Area Network) 400. The LAN
400 is a network which is connected between the disk array
apparatus 10 and management computer 500 to perform communicating
operation based on a protocol such as, e.g., TCP/IP. In this
connection, it is not necessarily required that the management
computer 500 be connected by a communication means such as the LAN
400, but the management computer 500 may be connected by means of a
communication line or bus line based on the SCSI (Small Computer
System Interface) Standard or in a peer-to-peer relationship.
The disk array apparatus 10, which is managed, e.g., by a system
center, data center or the like in a company or corporation,
functions as an apparatus for previously storing data to be
processed by the host computer 300. The host computer 300 in turn
is a computer which offers such a service as, e.g., an automatic
deposit/payment service in a bank or a homepage browsing service in
the Internet.
The disk array apparatus 10 and host computer 300 are connected by
the SAN 200. The SAN 200 is a network which is connected between
the disk array apparatus 10 and host computer 300 to communicate
with each other according to, e.g., a fiber channel protocol.
<Disk Array Apparatus>
The disk array apparatus 10 is a computer having a CPU (Central
Processing Unit) and a memory. When various programs are executed
under control of the CPU of the disk array apparatus 10, various
functions can be implemented. The disk array apparatus 10 performs
control over disk drives 51.alpha. and 51.beta. according to a
command received from the host computer 300. For example, when
receiving an input/output request of data sent from the host
computer 300, the apparatus perform performs data input/output
operation over the disk drives 51.alpha. and 51.beta.. The data is
stored in a logical volume as a storage area logically set on
physical storage areas provided by the disk drives 51.alpha. and
51.beta. of the disk array apparatus 10. The disk array apparatus
10 also sends or receives various commands to and from the host
computer 300 to manage the disk array apparatus 10.
The disk array apparatus 10 includes the basic casing 20 and one or
more of the additional casings 30, as has already been explained.
In the present embodiment, the basic casing 20 has a controller
100, disk drives 51.alpha., an FC-AL 150, port bypass switches 160,
and terminals 180. The controller 100 has a communication control
unit 110, a disk controller unit 120, a cache memory 62, and a bus
140. The controller 100 is mounted on the above control board 59.
The additional casing 30 has disk drives 51.beta., an FC-AL 150,
port bypass switches 160, converters 170 and terminals 180.
The communication control unit 110 has an interface for
communication with the host computer 300. The interface of the
communication control unit 110 is, for example, a host bus adaptor
(HBA) which connects the disk array apparatus 10 to the SAN 200. As
a result, the disk array apparatus 10 can transmit or receive
various data input/output commands or data to or from the host
computer 300. The interface of the communication control unit 110
is such a communication interface board 61 as mentioned above.
The bus 140 is wired between the communication control unit 110,
disk controller unit 120 and cache memory 62 to mutually connect
these. Data transfer between the communication control unit 110,
disk controller unit 120 and cache memory 62 is carried out via the
bus 140.
The cache memory 62 is a memory element to be used by the
communication control unit 110 and disk controller unit 120. The
cache memory 62 is used to temporarily store data transferred
between the communication control unit 110 and disk controller unit
120. Since the communication control unit 110 or disk controller
unit 120 uses the cache memory 62, the data writing or reading
operation can be efficiently carried out.
The terminal 180 provided to the basic casing 20 or additional
casing 30 is a metal fitting which connects together a connection
line in the basic casing 20 and a connection line in the additional
casing 30. Data or command transfer between the disk controller
unit 120 of the basic casing 20 and the disk drive 51.beta.
accommodated in the additional casing 30 is carried out via the
terminals 180.
The disk controller unit 120 executes operations of writing or
reading out data in or from the disk drives 51.alpha. and 51.beta.
in response to a data input/output request from the communication
control unit 110. The disk controller unit 120 writes data read out
from the disk drives 51.alpha. and 51.beta. in the cache memory 62.
Further, the disk controller unit 120 acquires data written in the
cache memory 62 by the communication control unit 110 and writes it
in the disk drives 51.alpha. and 51.beta..
The disk controller unit 120 may have such a function as to control
the disk drives 51.alpha. and 51.beta. at a so-called RAID
(Redundant Array of Inexpensive Disks) level (e.g., 0, 1, 5)
prescribed in the so-called RAID system.
Further, the disk controller unit 120 may perform management
control of a copy of data stored in the disk drives 51.alpha. and
51.beta. or backup control thereof.
In addition, for the purpose of preventing data disappearance or
loss due to occurrence of a disaster (disaster recovery), the disk
controller unit 120 may have a function (data replication function
(remote copy)) of storing a copy of data of the disk array
apparatus 10 at a primary site also in another disk array apparatus
installed at a secondary site.
The FC-AL 150, which is one of fiber channel systems (topologies),
acts to connect the disk controller unit 120 and disk drives
51.alpha. and 51.beta. by a loop-like connection line (transmission
line) to communicate with each other. In this connection, the disk
controller unit 120 and disk drives 51.alpha. and 51.beta. may be
communicably connected with each other by means of an FC-AL hub or
directly by a connection line such as a fiber channel cable.
The FC-AL 150 has a plurality of port bypass switches (PBC's) 160.
The PBC 160 has a main function of connecting the disk controller
unit 120 and a plurality of disk drives 51.alpha. and 51.beta. by
the FC-AL 150. The PBC 160, which is an electronic switch in the
form of a chip, also has a function of bypassing the disk
controller unit 120 and disk drives 51.alpha. and 51.beta. to
electrically remove the disk controller unit and disk drives
51.alpha. and 51.beta. from the FC-AL 150. More specifically, the
PBC 160 separates the disk drive 51, which became faulty, from the
FC-AL 150 thus enabling communication between another disk drive 51
and disk controller unit 120.
The PBC 160 also enables insertion and removal of the disk drive 51
with such a condition that the operation of the FC-AL 150 remains.
For example, when the disk drive 51 is newly mounted, the disk
drive 51 is incorporated into the FC-AL 150 to enable communication
with the disk controller unit 120. In this connection, the circuit
board of the PBC's 160 may be provided to the rack frame 11 of the
disk array apparatus 10, or all or some of the PBC's may be mounted
to the control board 59 or power controller board 56.
Accommodated in the disk array apparatus 10 are the plurality of
disk drives 51.alpha. and 51.beta. having different communication
interfaces (different communication Standards) for communication
with the disk controller unit 120. The communication Standards of
the communication interfaces possessed by the disk drives 51.alpha.
and 51.beta. include, for example, fiber channel (FC), SCSI1 (Small
Computer System Interface 1), SCSI2, SCSI3, ATA (AT Attachment) and
Serial ATA (SATA). In the present embodiment, the disk drives
51.alpha. have a fiber channel interface and the disk drives
51.beta. have an SATA interface. However, the present invention is
not limited to the specific example.
The converter 170 is a device which converts data or signal to make
the communication interface not adapted to the communication scheme
of the communication line with the disk controller unit 120 confirm
to the aforementioned communication scheme. The converter 170 is,
for example, an SCSI-ATA (IDE: Integrated Device Electronics)
converter, an FC-SATA converter, or an ATA (IDE)-SATA converter.
When the disk drive 51.beta. is connected to the FC-AL via the
converter 170, the disk drive 51.beta. can communicate with the
disk controller unit 120. The converter 170 may also be provided in
such a form as to be built in the disk drive 51.beta., or may also
be provided in such a form as to be installed outside of the disk
drive 51.beta..
<Management Computer>
The management computer 500 is a computer for maintaining and
managing the disk array apparatus 10 connected thereto by the LAN
400. The management computer 500 is, for example, a personal
computer, a workstation, a mainframe computer or the like.
The management computer 500 has a CPU, a memory and so on, and the
CPU of the management computer 500 performs general control over
the management computer 500 in such a manner that the computer
realizes various functions by executing various programs stored in
the memory.
When the operator operates the management computer 500, for
example, he can set the arrangements of the disk drives 51.alpha.
and 51.beta., manage or set logical volumes (capacity management,
capacity extension or reduction, assignment of the host computer
300, etc.), and so on. As an example of setting the arrangements of
the disk drives, addition or reduction of the number of disk drives
51.alpha. and 51.beta. or modification of the RAID configuration
(e.g., modification from RAID1 to RAID5) can be carried out.
Further, the confirmation of the operating mode of the disk array
apparatus 10 or the identification of a fault location can also be
done. These settings are realized by the operator who uses the Web
page offered by the Web server operated by the management computer
500 as a user interface. The management computer 500 may also be
provided in such a form as to be built in the disk array apparatus
10 or in such a form as to be installed outside thereof.
The management computer 500 may be used as a computer for exclusive
maintenance and management of the disk array apparatus 10 and disk
drives 51.alpha. and 51.beta., or such maintenance/management
functions may be provided to a general purpose computer.
From the above reasons, in the case of the disk array apparatus 10
of the present invention, various types of disk drives different in
communication interface, access speed, storage capacity and price
can be freely combined with the single disk controller unit, and
modification in the arrangement of an existing disk array apparatus
can be minimized and thus the existing apparatus can be effectively
used.
3. Circuit Configuration
In such a condition that the basic casing 20 and additional casing
30 are mounted in the rack frame 11, the boards and units mounted
in these casings 20 and 30 are wired by internal wiring lines or
circuits (not shown) provided to the rack frame 11 or by external
wiring lines to thereby establish such a circuit as shown in FIG.
6. In this drawing, thick lines indicate the FC-AL's 150, thin
lines indicate the control lines 48, and dashed lines indicate
power supply lines 49, respectively. Provided on the FC-AL's 150
are terminals (e.g., connectors) 190 for connection with the disk
drives 51.alpha. and 51.beta. and the boards and units of the disk
controller unit 120. The disk controller unit 120 is provided in
the form of a circuit including a CPU, a protocol control chip,
memories such as RAM and ROM and mounted on the control board 59;
and functions to control and monitor the disk drives 51.alpha. and
51.beta. mounted in the basic casing 20 and additional casings A
and B (30).
A main switch 85 is provided, e.g., on the front side of the basic
casing 20, so that, when the control board 59 is mounted to the
basic casing 20 for example, an output signal line 87 of the main
switch 85 is connected to the disk controller unit 120. In this
connection, the main switch 85 may also be provided to the rack
frame 11, in which case, the basic casing 20 is mounted to the rack
frame 11. For this reason, the output signal line 87 can also be
connected to the disk controller unit 120.
A power controller 81 is mounted on the power controller board 56.
The power controller 81 has memories such as CPU, RAM and ROM and
also has various types of control chips. The power controller 81
has wiring lines connected to the wind-assisted cooling fan unit 58
and AC/DC power supply 57. The power controller 81 controls and
monitors such boards and units mounted in the basic casing 20 and
additional casings A and B (30) as the wind-assisted cooling fan
unit 58, AC/DC power supply 57 and disk drives 51.alpha. and
51.beta..
The power controller 81 for each of the casings 20 and 30 is
connected directly to the disk controller unit 120 via the control
line 48. The power controller 81 may also be connected to the disk
controller unit 120 via an SES drive to be explained later.
The power controller 81, in response to a power supply signal or
power cut-off signal of the disk drives 51.alpha. and 51.beta.
received from the disk controller unit 120, transmits to the AC/DC
power supply 5 a signal indicative of power supply to the
respective disk drives 51.alpha. and 51.beta. or a signal
indicative of power cut-off to the disk drives 51.alpha. and
51.beta.. As a result, the AC/DC power supply 57 can supply power
to the disk drives 51.alpha. and 51.beta. or can stop power supply
thereto.
At the same time, according to the operating modes of the disk
drives 51.alpha. and 51.beta. accommodated in the casings, the
power controller 81 controls the rotational speed of the cooling
fan 66. In this connection, the control of the rotational speed of
the cooling fan 66 may be carried out in units of each of the disk
drives 51.alpha. and 51.beta. or in units of each casing. The
control of the rotational speed of the cooling fan enables
reduction of power consumption of the apparatus. Further, since the
rotational speed of the cooling fan is controlled depending on the
operating modes of the disk drives 51.alpha. and 51.beta., the
present disk array apparatus can realize noise prevention more
effectively than a disk array apparatus not for controlling the
rotational speed.
4. Operation
<Operating Mode of Disk Drive>
The disk drive 51, when receiving a command from the disk
controller unit 120, is switched to any one of operating modes of
"ready", "not ready" and "power off". The disk drive 51 operating
in the "ready" mode can accept read/write command of data sent from
the disk controller unit 120. The disk 73 of the disk drive 51
operating in the "ready" mode is rotating with a rotational speed
necessary for data reading/writing (spin up state). The average
power consumption of the disk drive 51 becomes maximum when the
disk drive is operating in the "ready" of the above three
modes.
When the disk drive 51 is operating in the "not ready" mode, the
disk drive 51 is not rotating with a rotational speed necessary for
the data reading/wring (spin down state). The disk drive 51
operating in the "not ready" mode cannot accept a command relating
to the data reading/writing, but can accept a specific type of
command such as, e.g., a command indicative of shift to the "ready"
mode. The average power consumption of the disk drive 51 operating
in the "not ready" mode is less than that in the "ready" mode.
When the disk drive 51 is in the "power off" mode, the disk drive
51 cannot accept a command sent from the disk controller unit 120.
Further, the rotation of the disk 73 of the disk drive 51 is
completely stopped. The average power consumption of the disk drive
51 is zero in the "power off" mode.
The aforementioned operating mode of the disk drive 51 can be
changed, for example, by an operator who operates a setting display
screen presented by a software program run by the management
computer 500. An example of such setting screen is shown in FIG. 7.
Since the operating mode of each of the disk drives 51 can be
controlled on the setting screen, the operation and management of
the apparatus can be improved.
The scheme of the communication interface of the disk drive 51 in
FIG. 7 can be acquired by the following method. That is, when the
disk controller unit 120 inquires the disk drive 51 accommodated in
the basic casing 20 and additional casing 30 via the FC-AL 150
(e.g., by polling), the disk controller unit can know the scheme
(standard) of the communication interface of the each disk drive
51. For example, when a command is sent to the each disk drive 51,
the type of the communication interface scheme is set to be
informed from the disk drive 51. The disk controller unit 120
stores the type of the communication interface Standard informed
from the disk drive 51 in a disk drive management table as
associated with the corresponding disk drive 51. The disk drive
management table is stored, for example, in the memory or the disk
drive 51. FIG. 8 shows an example of the disk drive management
table. Recorded in the disk drive management table are identifiers
of the disk drives 51 accommodated in each casing, communication
interface schemes of the disk drives 51, and operating modes of the
disk drives 51. In this connection, the above inquiry may be
carried out when the disk array apparatus 10 is operated or when
the user mounts the disk drive 51 in the casing 20 or 30.
With it, the disk controller unit 120 can control the operating
mode of each disk drive. Further, the disk controller unit 120 can
also control such operating mode in units of a group of disk drives
or in units of casing. As a result, the disk drives can be grouped
according to their usage purpose to form groups of drives or a
casing for exclusive backup or fix contents which can temporarily
save power. For example, such drives having a short life as SATA
drives can be used as drives exclusively for backup or fix
contents, such drives can be collectively controlled so that the
drives are put in the "power off" mode when not used or are
operated in the "ready" mode as necessary. As a result, not only
the use power can be reduced but also the life of the drives can be
unified and the average life of the drives can be secured, thus
increasing its maintenance efficiency. Furthermore, since the
operating modes of the disk drives can be controlled in units of
disk drive group, the operation and management of the apparatus can
also be improved.
<SES Drive>
Shown in FIG. 9 is an example when the disk drives 1 to 4
(51.alpha.) of the additional casing A 30 are used as SES drives.
In the present embodiment, it is assumed that the power controller
81 and disk controller unit 120 are connected by the SES drives.
The word "SES (SCSI Enclosure Services) drive" refers to such a
disk drive 51 that causes the disk controller unit 120 and the
power controller 81 for control of the power supply of the disk
drive 51 to be connected to each other communicably with each
other.
The SES drive has an SES (SCSI Enclosure Services) or ESI
(Enclosure Service I/F) prescribed in SCSI3 (Small Computer System
Interface 3) Standard. And the SES or ESI function can be activated
by connecting predetermined signal pins of the interface connector
79.
In the present embodiment, the disk drives 1 to 4 (51.alpha.) of
the additional casing A 30, i.e., FC drives are employed as SES
drives as shown in FIG. 9, but the disk drives 51 having another
communication interface may be used as the SES drives. Further, one
or a plurality of disk drives 51 may be used as SES drives. In the
present embodiment, the disk drives 5 to 8 (51.beta.) of the
additional casing A 30 as shown in FIG. 9 are of a SATA type.
In this way, since the SES function is provided to the specific
disk drive(s) 51, the need for provision of the control line 48 for
connection between the disk controller unit 120 and power
controller 81 can be eliminated. Further, The disk controller unit
120 can control the operating mode of another disk drive via the
SES drive.
When the SES drives are fixed to certain specific disk drives 51 as
mentioned above, the life of the disk drives 51 can be shortened
remarkably. To avoid this, it is considered to operate as
rotationally shifted the disk drives 51 functioning as the SES
drives. By operating the disk drives 51 as rotationally shifted in
this way, the life of the SES drives can be prolonged. Explanation
will next be made as to the rotational shift use of the SES
drives.
<Rotational Shift of SES Drives>
Explanation will be made as to a mechanism wherein SES drives in
the additional casing A 30 having the SATA drives alone housed
therein are shifted by rotation under control of a software
program, by referring to FIG. 10. The drawing shows a circuit
configuration of the additional casing A 30 having the SATA disk
drives (disk drive A to F) (51.beta.) housed therein.
A signal for control of power or the like is applied to a terminal
1 (190) from the basic casing 20 via the FC-AL 150. The signal
arrives at the power controller 81 via a terminal 3 (190), SES
drive (SATA drive A) 51.beta. and control line 48. At this time,
since the SATA drive A (51.beta.) is operating in the "ready" or
"not ready" mode, the signal for control of power or the like can
arrive at the power controller 81 via the disk drive A
(51.beta.).
The power controller 81, when receiving the power control signal
from the basic casing 20, controls the power supply to the power
fan, the rotational speed of the fan, etc. In this case, it is
assumed that power is already supplied to the SATA drive A
(51.beta.), power controller 81 and cooling fan 66 in an initial
state. Further the cooling fan 66 is operating in a
low-power-consumption mode.
When receiving a signal from the basic casing 20 to the additional
casing 30 to put the respective disk drives 51.beta. in the "ready"
mode, the power controller 81 changes the rotational speed of the
cooling fan 66 to a value in its normal operation and controls
switches SW2 to SW6 (195) to start power supply to the SATA drives
B-F (51.beta.).
Explanation will next be made as to how the power controller 81
changes the SES drive from the SATA drive A (51.beta.) to the SATA
drive B (51.beta.). FIG. 11 shows an example of a SES drive
changing procedure. As shown in FIG. 11, when receiving a signal
from the basic casing 20 to change the SES drive to another disk
drive 51.beta. and to put the latter drive in the "power off" mode
(S1100), the power controller 81 controls the switches SW1 and SW3
to SW6 (195) to stop power supply to the SATA drive A (51.beta.)
and to the SATA drives C-F (51.beta.) (S1101). Thereafter, the
operation of the SATA drive B is controlled to be in the "not
ready" mode (S1102) and the rotational speed of the cooling fan 66
is operated in the low-power-consumption mode (S1103), whereby the
additional casing 30 is put in the "power off" mode
(low-power-consumption operational mode). Next, when a signal for
control of power or the like comes from the basic casing 20, the
signal is transmitted to the power controller 81 via the SATA drive
B (51.beta.).
In this connection, the apparatus is designed so that, in response
to operator's instruction, the signal indicative of the change of
the SES drive to be received by the power controller 81 can be
transmitted to the power controller 81 from the basic casing 20,
but the signal can also be transmitted from the basic casing 20 at
the timing set by the user.
As mentioned above, when the power controller 81 receives the
signal indicative of change of the SES drive from the basic casing
20, the SES drive is changed from the SATA drive A (51.beta.) to
the SATA drive B (51.beta.). As the SES drive changing operation is
carried out sequentially from the SATA drive A (51.beta.) to
another SATA drive (51.beta.), the SES drive is sequentially
changed. Since the SES drive is sequentially changed in this way,
the lives of the disk drives 51.beta. can be made equal to each
other. However, the method of shifting the SES drive by rotation is
not limited to the above specific method, but another method can be
considered readily by those skilled in the art in the form of a
circuit configuration or the like.
<Basic Operation of Disk Array Apparatus>
Since the disk controller unit 120 communicates with the disk drive
51 housed in the basic casing 20 and additional casing A 30 via the
FC-AL 150, the disk controller unit 120 can know whether disk drive
51 is in any of the modes "ready", "not ready" and "power off".
Further, the disk controller unit 120 transmits a command to the
disk drive 51 to control the operation of the disk drive 51. In
this connection, the communication for the mode grasp and control
is carried out according to a protocol such as FC-AL or FCP (Fiber
Channel Protocol for SCSI). The disk controller unit 120 also
controls the cooling ability of the cooling fan 66 according to the
operational mode of the disk drive unit 52.
Such control is carried out, for example, when the user wants to
change the operational mode of a specific disk drive 51 on such a
setting display screen as shown in FIG. 7 or when a data write/read
request is issued from the host computer 300 to the disk drive 51
in the "power off" mode. Such control is also carried out even when
data stored in the disk drive 51 (put in the "ready" mode) is to be
stored in the disk drive 51 (in the "power off" mode) for exclusive
backup in response to user's instruction or the like. Explanation
will be made below in connection with an example of a processing
sequence wherein, in response to user's backup instruction or the
like, how the operation of the disk drive 51 and the cooling
ability of the cooling device are controlled.
FIG. 12 shows a flow chart for explaining a processing sequence to
control the operation of the disk drive and the cooling ability of
the cooling fan 66.
The management computer 500 first transmits a backup request to the
disk array apparatus 10 via the LAN 400 for backup. The disk array
apparatus 10, when receiving the backup request, refers to the disk
drive management table stored in the memory or disk drive 51,
confirms the operational mode of the disk drive 51.beta. as a
backup destination, and starts its backup operation. In this case,
it is assumed in its initial state that the disk drive 51.beta.
housed in the additional casing A 30 is put in the "power off" mode
and the cooling fan 66 is operating in the "low-power-consumption"
mode. It is also assumed that the disk drive 51.alpha. housed in
the basic casing 20 is put in the "ready" mode and the cooling fan
66 is operated in the normal mode.
When the disk array apparatus 10 receives the backup request
(S1200), the apparatus transmits a command to the power controller
81 of the additional casing A 30 via the control line 48 to
increase the rotational speed of the cooling fan 66. The power
controller 81, when receiving the signal, increase the rotational
speed of the cooling fan 66 (S1201). Further, the rotational speed
of the cooling fan 66 at this stage may be previously increased to
a level necessary for dissipation of heat to be generated when the
disk drive 51.beta. specified by the operator is put eventually in
the "ready" mode. Thereby, the operation of the disk drive 51.beta.
is shifted to the "ready" mode faster than the increase of the
rotational speed of the cooling fan 66, thus preventing the
temperature increase within the casing. Also the rotational speed
of the cooling fan 66 may be gradually increased depending on the
rising condition of the disk drives 51.beta. specified by the
operator. When it is desired to adjust not the rotational speed but
the number of driven cooling fans 66, it is also possible to
gradually increase the number of cooling fan 66 to be driven
according to the rising condition of the disk drive 51.beta.. In
this way, since the cooling fans 66 can be driven in a condition
sufficient in the then circumstances, power saving and noise
reduction can be realized more effectively.
The disk controller unit 120 then transmits a command to the power
controller 81 via the control line 48 to instruct the power
controller 81 to start power supply to the disk drive 51.beta.
specified by the operator. The power controller 81, when receiving
the command, controls the AC/DC power supply 57 to start the power
supply to the disk drive 51.beta. specified by the operator
(S1202). As result, the disk drive 51.beta. is shifted from the
"not ready" mode to the "ready" mode.
The disk controller unit 120 is monitoring the operational state of
the disk drive 51.beta. by inquiry (e.g., by polling) via the
control line 48. And as soon as the disk controller unit 120
recognizes the fact that the disk drive 51.beta. was put in such a
condition as able to read or write data, the disk controller unit
starts operation of causing the data stored in the disk drive
51.alpha. specified by the operator to be stored in the associated
disk drive 51.beta. (S1203). When the disk controller unit 120
recognize the end of the above operation, the disk controller unit
transmits a command to the disk drive 51.beta. via the control line
48 to shift the disk drive 51.beta. from the "ready" mode to the
"power off" mode (S1204). As a result, the disk drive 51.beta. is
put in the "power off" mode (S1205).
The disk controller unit 120 is monitoring the operational state of
the disk drive 51.beta. by the inquiry via the control line 48. And
when recognizing the fact that the disk drive 51.beta. was shifted
to the "power off" mode, the disk controller unit 120 transmits a
command to the power controller 81 of the additional casing 30 via
the control line 48 to decrease the rotational speed of the cooling
fan 66 of the cooling fan unit 58 mounted in the additional casing
30 (S1206). When receiving the command, the power controller 81
reduces the rotational speed of the cooling fan 66, for example, by
decreasing a drive voltage for the cooling fan 66 (S1207) and
terminates its backup operation.
In this connection, such control can also be realized, for example,
by the disk drive 51.beta. which transmits a command to the cooling
fan unit 58 to reduce its rotational speed, and the control itself
can be carried out by the CPU mounted in the cooling fan unit 58.
The degree of reduction of the rotational speed of the cooling fan
66 may be determined to have a sufficient cooling capacity
depending on the operational mode of the disk drive 51.beta..
Further, the number of driven cooling fans 66 may be adjusted by
the power controller 81 which controls the AC/DC power supply 57
depending on the operational state of the disk drive 51.
Furthermore, the rotational speed of the cooling fan 66 can also be
controlled finely depending on the operational state of the disk
drive 51.beta. varying from time to time, by the disk controller
unit 120 or by the power controller 81 of the additional casing 30
which monitors the operational states of the disk drives 51.beta.
in real time or in short intervals. It is also possible to
automatically set the rotational speed at an optimum value based on
a temperature detected by a sensor or the like.
As has been explained above, since the operation of the disk drive
51 and the cooling ability of the cooling fan 66 can be controlled
at a necessary time such as backup, power saving and noise
reduction can be realized.
Although the explanation has been made in connection with the
present embodiment, the embodiment is given only for easy
understanding of the present invention and thus the present
invention is not limited to the specific example. The present
invention can be modified and changed without departing from the
subject matter of the invention, and obviously, numerous
equivalents thereof are included in the present invention.
5. Another Embodiment
Various functions of the disk controller unit 120 and power
controller 81 as mentioned above are not always required to be
provided in such a manner as mentioned above. Thus provision of the
various functions to the disk controller unit 120 or power
controller 81 can be freely determined depending on various
circumstances.
The cooling device mounted in the basic casing 20 or additional
casing 30 is not limited to the aforementioned cooling fan unit 58,
but may be, for example, a water-cooling type cooler or a Peltier
(effect) element.
In another embodiment, the function of the host computer 300 for
measuring an access frequency to each disk drive 51 may be provided
to the disk array apparatus 10 so that, when the disk array
apparatus 10 judges that the access frequency to the disk drive 51
(such as SATA drive) usually operating in the "power off" mode
exceeded a predetermined threshold value, data stored in the
associated disk drive 51 is stored in the disk drive (e.g., FC
drive) 51 usually operating in the "ready" mode. As a result, the
lives of the drives can be averaged and thus its maintenance
efficiency can be increased.
The present invention can also be applied to a storage apparatus
other than the disk array apparatus, for example, even to not disk
drives but storage devices using semiconductor disks as storage
devices.
It should be further understood by those skilled in the art that
although the foregoing description has been made on embodiments of
the invention, the invention is not limited thereto and various
changes and modifications may be made without departing from the
spirit of the invention and the scope of the appended claims.
* * * * *
References